Conflicting Causes Of Psoriasis

By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) - Psoriasis is an inflammatory disease of the skin and joints. Unfortunately, there is no cure. What we need to understand is psoriasis is a condition that is frustrating to treat and certainly frustrating to live with.

Over the years, scientists have taken two different views on what triggers psoriasis. Some people have thought of it as an immune disorder that affects the skin. This is known as the "inside-out hypothesis." Others think it is a skin disorder that alters the immune system. That's called the "outside-in hypothesis."

If you look at the research most supports the concept that psoriasis causes the other immune system changes. This has major implications on research and how we are dealing with it.